class Solution {
public:
    int search(vector<int>& nums, int target) {
        int left = 0,right = nums.size()-1;
        while(target!=nums[mid]&&left <= right)
        {
            mid = (left+right)/2;
            if(nums[mid] == target)
            return mid + 1;
            else
            {
                if(nums[mid] < target)
                left = mid + 1;
                else
                right = mid -1;
            }
        }
        return 0;
    }
};